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arXiv · 1907.03696

Features in cosmic-ray lepton data unveil the properties of nearby cosmic accelerators

Ottavio Fornieri·Daniele Gaggero·Dario Grasso
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Abstract

We present a comprehensive discussion about the origin of the features in the leptonic component of the cosmic-ray spectrum. Working in the framework of a up-to-date CR transport scenario tuned on the most recent AMS-02 and Voyager data, we show that the prominent features recently found in the positron and in the all-electron spectra by several experiments are explained in a scenario in which pulsar wind nebulae (PWNe) are the dominant sources of the positron flux, and nearby supernova remnants shape the high-energy peak of the electron spectrum. In particular we argue that the drop-off in positron spectrum found by AMS-02 at $\sim 300$ GeV can be explained --- under different assumptions --- in terms of a prominent PWN that provides the bulk of the observed positrons in the $\sim 100$ GeV domain, on top of the contribution from a large number of older objects. Finally, we turn our attention to the spectral softening at $\sim 1$ TeV in the all-lepton spectrum, recently reported by several experiments, showing that it requires the presence of a nearby supernova remnant at its final stage.

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Ottavio Fornieri, Daniele Gaggero, Dario Grasso. 2019-07-08. Features in cosmic-ray lepton data unveil the properties of nearby cosmic accelerators. https://doi.org/10.1088/1475-7516%2F2020%2F02%2F009

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